Scott, Would it be reasonable to say that:
D2RQ takes everything in a database as a table, but if the table has no primary key then it would not create correct instances out of records in the object such as view or materialized view? It seems that way to me. I create a table, without primary key specification, it generates the similar result out of the table. Mingzhen On Apr 10, 1:48 pm, mwz <[email protected]> wrote: > Scott, > > Thank you for your suggestion. But I checked the -Mapping.owl file, > and found the definition for the materialized view in my case as > following: > > For ClassMap: > > <d2rq:ClassMap rdf:ID="MWEI_TESTMVIEW"> > <d2rq:class rdf:resource="http://www.owl-ontologies.com/ > mySchema.owl#MWEI_TESTMVIEW"/> > <d2rq:uriPattern>http://www.owl-ontologies.com/ > myDatabase.owl#MWEI.TESTMVIEW</d2rq:uriPattern> > <d2rq:dataStorage rdf:resource="#database"/> > <rdfs:comment>Derived from table 'MWEI.TESTMVIEW' > Sorry, I don't know which columns to put into the uriPattern > because the table doesn't have a primary key</rdfs:comment> > </d2rq:ClassMap> > > For propertyBridge: > > <d2rq:PropertyBridge rdf:ID="TESTMVIEW_LEN"> > <d2rq:property rdf:resource="http://www.owl-ontologies.com/ > mySchema.owl#TESTMVIEW_LEN"/> > <d2rq:datatype rdf:resource="http://www.w3.org/2001/ > XMLSchema#decimal"/> > <d2rq:column>MWEI.TESTMVIEW.LEN</d2rq:column> > <d2rq:belongsToClassMap> > <d2rq:ClassMap rdf:ID="MWEI_TESTMVIEW"> > <d2rq:class rdf:resource="http://www.owl-ontologies.com/ > mySchema.owl#MWEI_TESTMVIEW"/> > <d2rq:uriPattern>http://www.owl-ontologies.com/ > myDatabase.owl#MWEI.TESTMVIEW</d2rq:uriPattern> > <d2rq:dataStorage rdf:resource="#database"/> > <rdfs:comment>Derived from table 'MWEI.TESTMVIEW' > Sorry, I don't know which columns to put into the uriPattern > because the table doesn't have a primary key</rdfs:comment> > </d2rq:ClassMap> > </d2rq:belongsToClassMap> > </d2rq:PropertyBridge> > > <d2rq:PropertyBridge rdf:ID="TESTMVIEW_ITEM_ID"> > <d2rq:property rdf:resource="http://www.owl-ontologies.com/ > mySchema.owl#TESTMVIEW_ITEM_ID"/> > <d2rq:datatype rdf:resource="http://www.w3.org/2001/ > XMLSchema#decimal"/> > <d2rq:column>MWEI.TESTMVIEW.ITEM_ID</d2rq:column> > <d2rq:belongsToClassMap rdf:resource="#MWEI_TESTMVIEW"/> > </d2rq:PropertyBridge> > > I am trying to set up views with primary keys and see if it works with > D2RQ. Thank you. > > Mingzhen > > On Apr 10, 11:52 am, Scott Henninger <[email protected]> > wrote: > > > > > Mingzhen; The D2RQ mapping created by Composer is a default mapping. > > You can manipulate how this mapping occurs through the -Mapping.owl > > file and -Schema.owl files. For example, you can specify how > > properties (ontology world) are created from tables (relational world) > > through instances of the PropertyBridge and ClassMap properties. > > > For the most part, D2RQ only knows about tables, so you will need to > > re-create the view by manipulating the mapping or through post- > > processing - i.e. SPARQLMotion scripts. > > > In terms of this example, it seems to me that you can do this through > > the mapping. You'd create a class mapping (instance of ClassMap) for > > the view (my_view). Then two properties (instances of PropertyBridge) > > that are linked to my_view by the belongsToClassMap property. > > > To apply your new mapping, close the -Test.owl file and re-load. This > > file imports the schema and mapping file and will therefore apply the > > edited definitions. > > > For specifics on the mapping ontology, > > seehttp://www4.wiwiss.fu-berlin.de/bizer/d2rq/spec/#specification > > > -- Scott > > > On Apr 10, 10:52 am, mwz <[email protected]> wrote: > > > > I am using D2RQ to generate a rdf view for contents in an oracle > > > database. I found out TopBraid or D2RQ cannot process 'view' in oracle > > > correctly. The view is taken as a whole, so whatever records in a > > > view, it is taken as bags of values for different attributes. For > > > example, I have a materialized view that has five records as follow: > > > ITEM_ID,LEN > > > 871605,25668.5524219754 > > > 871607,25676.4279991913 > > > 871609,25676.4279991913 > > > 871611,25684.2896538871 > > > 871613,25684.2896538871 > > > > The Topbraid version shows the following information: > > > > schema:mWEI_TestMView has an instance db:MWEI.TestMView > > > db:MWEI.TestMView has two attribtues: > > > schema:TestMView_item_id that has values: 871605, 871607, 871609, > > > 871611, 871613 > > > schema:TestMView_len has values: 25668.5524219754, 25676.4279991913, > > > and 25684.2896538871. > > > > Sparql query shows that these values are not paired as in database. > > > > So view or materialized views are supposed to work this way? What > > > would be the solution? Thank you very much. > > > > Mingzhen- Hide quoted text - > > > - Show quoted text -- Hide quoted text - > > - Show quoted text - --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "TopBraid Composer Users" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/topbraid-composer-users?hl=en -~----------~----~----~----~------~----~------~--~---
